My two cents on the fair play hypocrisy
For me, everything that is not forbidden in the race should be allowed. Aru clearly saw that Froome had a mechanical and attacked, he stopped when the others didn't cooperate with him. Had him to justify the fact he attacked? Absolutely not.
Tour de France, as the other races are man AND bike races. Bike is 50% part of it. If you stress the bike you can have mechanical accidents, so it is lawful to use them at your advantage.
The other hand of the "unwritten rules" is that there are different application case. Nobody would've waited Sagan for the same thing in Roubaix. Nobody waited Dumoulin in Giro or Martin after the fall and there could be 300 different cases about that with different outcomes. What if, for example, Bardet or another competitor was already in front (like Sanchez in Bales 2010) when Aru attacking? Has the group to stop for Froome and let him gaining time?
So, race is race, a man AND bike race. In Tour, in Giro, in Roubaix, in every cycling race and attacking during a mechanical or a fall is not forbidden by rules. Let's stop this fair play hypocrisy

Tour de France, as the other races are man AND bike races. Bike is 50% part of it. If you stress the bike you can have mechanical accidents, so it is lawful to use them at your advantage.

Totally agree. It is clear that they wait for him because he's Froome and Team Sky. Nobody waited for Dan Martin in the descent of Mont du Chat, or Contador when he crashed in Col de la Biche. Double standard. Fortunately, there are still defiant riders like Aru or Bardet.